I have searched and installed a lot of icon sets, but after a while I was surprised to see how big these packages were and decided to return to the basic set "Lubuntu Box". But I have tried to delete all the big packages that I considered useless from usr/share/icons and from ~/.icons. And something went wrong: a lot of applications are without icon now, like the network tray icon, DeaDBeef, and many others

I have reinstalled lubuntu-artwork-12-10 without result.
For some reason "malys-uniblu" is the icon set that still covers a lot of apps that other icon sets do not.

Edit after answer advising Clean your cache, then use apt-get install -f and then install Hi Color first : how to clear cache is not clear to me but i did some stuff found on askubuntu here; apt-get install -f gives a lot of errors posted below; but especially: how to install hi colors? i mean they are already installed; removing it first involves removing a huge number off apps; just reinstalling in synaptic gives the errors posted above.

was there a happy ending to this story?
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user25656Jun 18 '13 at 14:54

@vasa1 - yes. the accepted answer was edited by me and reflects the steps to solve this. the question is way too long, for it contains different stages of the effort to solve this, as the initial answer didn't work in fact. but it was the necessary base for the rest: using the live cd to restore it all
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cipricusJun 18 '13 at 21:17

1 Answer
1

The Lubuntu icon theme doesn't come with all icons ever made, it inherits elementary, which inherits gnome, which inherits hi-color icons, to make up for the ones it doesn't have.

If you deleted those folders you'll be missing icons.

HiColor for example is a must, this is because it provides a "base" for all icons as you can read from the description of the package hicolor-icon-theme. The Gnome icon theme (gnome-icon-theme) depends on this package, and most GTK icon sets inherit icons from both.

Now this sounds crazy but, might as well just remove all the icons that you have either installed by APT or manually installed. Clean your cache, then use apt-get install -f and then install Hi Color first.

Edit after testing:

If the above doesn't work due to errors mentioned in the edited question, boot from a live cd or usb and copy the folder usr/share/icons (of the cd/usb system). Save it on the desktop folder of your main hdd installation. Then boot normally and replace the folder usr/share/icons (of your main installation) with the folder icons that now should be on your desktop. Then, try reinstalling hicolor-icon-theme, gnome-icon-theme, and elementary-icon-theme in Synaptic Manager (and also other stuff that seemes related to icons and artwork in Lubuntu, just to be sure): that should now work without previous errors. But
still the missing icons would not appear, in the sense that they are not applied for the programs in usr/share/applications (and therefore in menus) until these programs are themselves reinstalled.

Reinstalling the program from deb seems to be enough, but this may depend on the program. In Synaptic, at least for some programs, complete removal and re-installation is needed. The situation may vary from case to case: for example, reinstalling DeaDBeef from deb solved it, Brasero was fixed by complete removal and reinstallation, VLC by full reinstallation but only after removing completely and reinstalling vlc-data, etc.